Definition of Meningitis, bacterial

Meningitis, bacterial: Inflammation of the meninges due to a bacterial infection. Haemophilus influenzae type B (HIB) was formerly the leading cause of bacterial meningitis before the 1990s, but childhood vaccinationshave reduced the occurrence of meningitis due to H. influenzae. Streptococcus pneumoniae and Neisseria meningitidis are the leading causes of bacterial meningitis. High fever, headache, and stiff neck are common symptoms of bacterial meningitis in anyone over the age of 2 years. In newborns and small infants, the classic symptoms of fever, headache, and neck stiffness may be absent and the infant may only appear to be inactive, irritable, vomiting, or feeding poorly. A sample of spinal fluid obtained via lumbar puncture can be examined to confirm the diagnosis and fully identify the bacteria involved and their antibiotic sensitivity. Treatment is started as early as possible, in the hospital. Appropriate antibiotic treatment has reduced the risk of death from most common types of bacterial meningitis to below 15 percent, although the risk is higher among the 'elderly.